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陕西工学院学报 2001年第2期17卷 13-15页

作者：张宏希陕西工学院电工电子实验中心陕西汉中723003

给出一种RC电路时间常数的增大方法 ,该方法基于晶体三极管基极和集电极电流之间的关系iC=βiB,可获得用小电阻。

关键词： RC电路时间常数增大方法晶体三极管基极集电极电流分配

计提奖励方式下提前竣工奖励标准制定问题研究

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建筑经济 2016年第10期37卷 62-65页

作者：柯洪张熙天津理工大学管理学院天津300384

基于业主在专用合同条款中制定提前竣工奖励标准的视角,比较计提和每日历天奖励两种奖励方式的激励效果、承包商满意程度等,确定计提奖励方式为合理的提前竣工奖励方式。在此基础上,确定计提基数及基数的合理比例,并通过案例分析计提奖... 详细信息

基于业主在专用合同条款中制定提前竣工奖励标准的视角,比较计提和每日历天奖励两种奖励方式的激励效果、承包商满意程度等,确定计提奖励方式为合理的提前竣工奖励方式。在此基础上,确定计提基数及基数的合理比例,并通过案例分析计提奖励方式下提前竣工奖励标准制定方法。

关键词：提前竣工计提奖励标准制定合同条款

High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin He Lin-Sen Ye xiao-Feng Yang Jia-Jia zhang hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

基于DC-MSV的动态套期保值模型及实证研究

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系统管理学报 2008年第4期17卷 409-417页

作者：周颖张红喜迟国泰大连理工大学管理学院大连116024

根据现货与期货价格随机波动的特点,引入一种新的动态相关系数,建立了基于DC-MSV的动态套期保值模型。通过DC-MSV模型来估计动态的套期保值比率。其具体特色:①通过建立套期保值比率与具有时变特征的收益率标准差的函数关系,揭示了最优... 详细信息

根据现货与期货价格随机波动的特点,引入一种新的动态相关系数,建立了基于DC-MSV的动态套期保值模型。通过DC-MSV模型来估计动态的套期保值比率。其具体特色:①通过建立套期保值比率与具有时变特征的收益率标准差的函数关系,揭示了最优套期保值比率的时变特征;②通过建立具有时变特征的收益率相关系数的函数关系的DC-MSV模型,揭示了推动资产价格波动因素的有效信息,完整地估计了资产收益波动的交叉相关性;③实证研究表明,该模型优于现有流行的套期保值模型。通过建立基于沪铜现货和期货的最小方差套期比的动态套期保值策略进行实证研究。研究结果表明,套期保值模型在样本期外和样本期内套期保值效果都明显优于Na ve和OLS套期保值策略。

关键词：动态套期保值 DC-MSV模型最小方差套期比套期保值效率

CoPSe nanoparticles confined in nitrogen-doped dual carbon network towards high-performance lithium/potassium ion batteries

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Chinese Chemical Letters 2025年第1期36卷 568-573页

作者： Zhong-Hui Sun Yu-Qi zhang Zhen-Yi Gu Dong-Yang Qu hong-Yu Guan xing-Long Wu Guangdong Engineering Technology Research Center for Photoelectric Sensing Materials and Devices c/o School of Chemistry and Chemical EngineeringGuangzhou UniversityGuangzhou 510006China MOE Key Laboratory for UV Light-Emitting Materials and Technology Northeast Normal UniversityChangchun 130024China

The metal ion batteries have gained widespread attention for wearable electronics due to their competitive energy density and long cycling *** the advanced anode materials is significant for next generation energy storage ***,severe electrode volume changes and sluggish redox kinetics are the critical problems for lithium/potassium ion batteries(LIBs/PIBs)towards large-scale ***,we prepare a novel anode material,which consists of reduced graphene oxide wrapping one-dimensional(1D)N-doped porous carbon nanotube with cobalt phosphoselenide(CoPSe)nanoparticles embedded inside them(r GO@Co PSe/NC).Benefited from the dual carbon decorations and ultrafine nanoparticles structure,it achieves a reversible capacity of 245 mAh/g at 5 A/g after 2000 cycles for LIBs and 215 mAh/g at 1 A/g after 500 cycles for *** pseudocapacitance and GITT measurements are used to investigate the electrochemical kinetics of r GO@Co PSe/NC for *** addition,the lithium ion full cell also shows good electrochemical performance when paired with high capacity LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2) *** work provides a feasible electrode design strategy for high-efficiency metal ion batteries based on multidimensional nanoarchitecture engineering and composition tailoring.

关键词： Cobalt phosphoselenide Lithium-ion batteries Potassium-ion batteries Reduced graphene oxide Structural stability Full cell

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从“少阳主骨”论骨质疏松症

中华中医药杂志 2019年第6期34卷 2381-2383页

作者：王庆谚郑洪新张虹玺辽宁中医药大学沈阳110032 辽宁中医药大学附属第三医院沈阳110003

'少阳主骨'这一理论根源于《黄帝内经》,足少阳之脉循行周身大部分骨节,少阳居半表半里之位,为人身阴阳气机升降出入开阖的枢纽。少阳之气刚,骨之质亦刚,故少阳与骨的关系密切。历代医家多从'肾主骨生髓'理论对骨质疏松症(OP)展开阐释,... 详细信息

'少阳主骨'这一理论根源于《黄帝内经》,足少阳之脉循行周身大部分骨节,少阳居半表半里之位,为人身阴阳气机升降出入开阖的枢纽。少阳之气刚,骨之质亦刚,故少阳与骨的关系密切。历代医家多从'肾主骨生髓'理论对骨质疏松症(OP)展开阐释,而'少阳主骨'理论存在千年,究其与OP之间的关系意义重大。

关键词：少阳主骨肾主骨骨质疏松症

Quantitative analysis of influencing factors to aerosol pH and its responses to PM_(2.5)and O_(3)pollution in a coastal city

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Journal of Environmental Sciences 2025年第5期151卷 284-297页

作者： Ke Xu Liqian Yin Qiaoling Chen Dan Liao xiaoting Ji Keran zhang Yu Wu Lingling Xu Mengren Li xiaolong Fan Fuwang zhang Zhi Huang Jinsheng Chen Youwei hong Center for Excellence in Regional Atmospheric Environment Key Lab of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China School of Life Sciences Hebei UniversityBaoding 071000China University of Chinese Academy of Sciences Beijing 100049China College of Resources and Environment Fujian Agriculture and Forest UniversityFuzhou 350002China College of Chemical Engineering Huaqiao UniversityXiamen 361021China College of Environment and Public Health Xiamen Huaxia UniversityXiamen 361024China Fujian Key Laboratory of Atmospheric Ozone Pollution Prevention Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Environmental Monitoring Center of Fujian Fuzhou 350003China xiamen Institute of Environmental Science Xiamen 361021China

Aerosol acidity(pH)plays an important role in the multiphase chemical processes of atmospheric *** this study,we demonstrated the seasonal trends of aerosol pH calculated with the ISORROPIA-II model in a coastal city of southeast *** performed quantitative analysis on the various influencing factors on aerosol pH,and explored the responses of aerosol pH to different PM_(2.5)and O_(3)pollution *** results showed that the average aerosol pH was 2.92±0.61,following the order of winter>spring>summer>*** tests revealed that SO_(4)^(2−),NH_(x),T and RH triggered the variations of aerosol *** analysis results showed that T(37.9%-51.2%)was the main factors affecting pH variations in four seasons,followed by SO_(4)^(2−)(6.1%-23.7%),NH_(x)(7.2%-22.2%)and RH(0–14.2%).Totally,annual mean meteorological factors(52.9%)and chemical compositions(41.3%)commonly contributed the aerosolpH in the coastal *** concentrations of PM_(2.5)was positively correlated with aerosol liquid water content(R^(2)=0.53)and aerosol pH(R^(2)=0.26),indicating that the increase in pH was related with the elevated NH_(4)NO_(3)and decreased SO_(4)^(2−),and also the changes of T and *** O_(x)(O_(3)+NO_(2))was moderately correlated with aerosol pH(R^(2)=-0.48),attributable to the fact that the proportion of SO_(4)^(2−)increased under high T and low RH *** study strengthened our understanding of the contributions of influencing factors to aerosol pH,and also provided scientific evidences for chemical processes of atmospheric particles in coastal areas.

关键词： Aerosol acidity Aerosol liquid water Fine particular matter(PM_(2.5)) Ozone(O_(3)) Coastal city

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我国非法证据排除规则的可操作性拷问

铁道警官高等专科学校学报 2011年第6期21卷 48-51页

作者：张弘西安交通大学法学院陕西西安710049

我国非法证据排除规则确立了刑讯逼供证据坚决排除的基本原则,意味着我国刑事司法向人权保障的积极迈进。在实务操作中,可行性是能否贯彻立法精神的关键指标。我国非法证据排除规则还存在若干可行性疑问,在非法证据界定、非法物证考量... 详细信息

我国非法证据排除规则确立了刑讯逼供证据坚决排除的基本原则,意味着我国刑事司法向人权保障的积极迈进。在实务操作中,可行性是能否贯彻立法精神的关键指标。我国非法证据排除规则还存在若干可行性疑问,在非法证据界定、非法物证考量、毒树之果效力、警察出庭保障、被告人举证、讯问全程录音录像等方面尚待进一步细化完善,以增强可操作性,防止规则被虚置。

关键词：非法证据规则非法证据可操作性

线粒体DNA突变与大鼠乙醇性肝纤维化的关系

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毒理学杂志 2008年第2期22卷 114-116页

作者：朱孔锡刘莉张喜红刘斌王红娟阎明山东大学第二医院消化内科山东济南250033 山东大学齐鲁医院消化内科

目的对线粒体DNA ATP酶6,8基因(mtDNA ATPase 6,8gene)突变与乙醇性肝损伤发生发展之间的关系进行研究,从一个新的角度对乙醇性肝病(ALD)的发病机制进行探讨。方法应用乙醇加橄榄油灌胃的方式建立大鼠乙醇性肝损伤动物模型并设对照组(... 详细信息

目的对线粒体DNA ATP酶6,8基因(mtDNA ATPase 6,8gene)突变与乙醇性肝损伤发生发展之间的关系进行研究,从一个新的角度对乙醇性肝病(ALD)的发病机制进行探讨。方法应用乙醇加橄榄油灌胃的方式建立大鼠乙醇性肝损伤动物模型并设对照组(等量生理盐水),成模后进行肝脏组织学观察,PCR扩增各组线粒体DNA ATPase 6,8基因并进行序列测定。以生物发光法分别测定各组肝组织中ATP含量,判定ATPase 6,8基因突变对肝细胞内ATP能量合成的影响。结果模型组大鼠肝细胞线粒体出现形态学的改变;线粒体DNA ATPase 6亚基基因发现两处点突变;对照组未检出突变。模型组大鼠肝细胞内ATP含量明显降低(P<0.05)。结论持续过量的乙醇摄入可造成肝细胞线粒体形态和mtDNA ATPase基因突变,这可能是乙醇性肝损伤的重要发病机制。

关键词：乙醇性肝病线粒体DNA ATP酶基因基因突变

Tandem asymmetric dearomatized functionalization reaction of phenols with Evans-ynamides enabled by divergent electrophiles

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Science China Chemistry 2025年第2期68卷 649-660页

作者： Ying-Qi zhang Gan-Lu Qian Yun Liu Jia-Hui Li xin hong Zhou Xu Bo Zhou Long-Wu Ye State Key Laboratory of Physical Chemistry of Solid Surfaces Key Laboratory of Chemical Biology of Fujian Provinceand College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China Center of Chemistry for Frontier Technologies Department of ChemistryState Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 221004China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China State Key Laboratory of Organometallic Chemistry Chinese Academy of SciencesShanghai 200032China

Herein,we disclose a highly regio-/chemoselective tandem asymmetric dearomatized halofunctionalization reaction of phenoltethered ynamides with diverse electrophilic halogenation sources in a catalyst-free manner for the practical and rapid assembly of a series of halogenated spirocyclic ***,the related dearomatized selenation and protonation are also achieved,affording the corresponding selenated and protonated spirocycles in high ***,the enantioselectivities of these products can be perfectly induced by Evans auxiliaries(99%ees).Significantly,this protocol not only represents the first tandem asymmetric halofunctionalization reaction of phenol derivatives,but also constitutes the first asymmetric halogenation/selenation of *** calculations indicate a remote induction model of Evans chiral auxiliary-attached keteniminium.

关键词： alkynes cyclization dearomatization Evans chiral auxiliary spirocycles